Leptoclinides (Ascidiacea, Didemnidae) from Brazil: new records and two new species
Author
Oliveira, Livia M.
Author
Carvalho, João Paulo
Author
Rocha, Rosana M.
text
European Journal of Taxonomy
2019
2019-10-29
572
1
16
journal article
25024
10.5852/ejt.2019.572
0de36645-90d1-4bcb-bb46-3b84c1de037e
3526896
A28B6248-D883-4FBC-B30E-3CE6596C384F
Leptoclinides lotufoi
sp. nov.
urn:lsid:zoobank.org:act:
31D0C00F-2263-4826-8CEC-9782A1704D49
Fig. 3
Etymology
The name of this species is in homage to Dr Tito Lotufo for his studies in ascidian diversity in northeastern
Brazil
. He collected this material and lent it to us for this study.
Material examined
Holotype
BRAZIL
• 1 colony;
Rio de Janeiro
,
Angra Reis
,
Ilhota dos Porcos
;
22°58′46″ S
,
44°19′47″ W
;
10 m
depth
;
10 Oct. 1998
;
T.M.C. Lotufo
leg.; ColBio Tun 1245.
Description
The only colony found was attached to a exposed granitic substrate around
10 m
deep. This colony was encrusting and small (
2 cm
wide,
1 mm
thick), orange, but lost most of its color when fixed in formalin (
Fig. 3A
). The tunic is malleable and delicate, with a wide cloacal cavity that extends from the thorax to the region of the esophago-rectal peduncle. Only one common cloacal aperture was seen in this specimen; it is broad with a smooth margin. Spicules, in low density, almost unnoticeable, are mainly restricted to the surface layer of the tunic. Spicules are
20 to 30 µm
in diameter, with 10–12 (in cross section) conical, pointed rays (
Fig. 3B
). SEM images of the spicules could not be made because of their scarcity and the small size of the colony.
Fig. 3.
Leptoclinides lotufoi
sp. nov.
, holotype (ColBio Tun 1245).
A
. Preserved colony.
B
. Spicules under light microscope.
C
. Thorax.
D
. Abdomen.
E
. Larva. Scale bars: A = 0.5 cm; B = 30 µm; C–E = 0.1 mm.
Zooids are orangish, about
1.5 mm
long. Twelve muscle fibers run longitudinally along each side of the thorax. The oral siphon is
0.15–0.33 mm
long with six rounded lobes. The atrial aperture is very short and opens between the third and fourth rows of the pharyngeal stigmata. The pharyngeal stigmata formula is 10–12, 10, 10, 9–10 per half row. The lateral thoracic organ is round, not salient, usually at about the third row of stigmata, occasionally at the second row, close to the endostyle (
Fig. 3C
). The stomach is slightly elongated and is not overlapped by the intestinal loop. The testis has three oval follicles, overlain by three open turns of the sperm duct (
Fig. 3D
).
Most of the larvae we found were immature. Larvae are oval, yellowish, with about
0.8 mm
in trunk length, without vesicles. The tail curves about halfway around the trunk. There are three anterior adhesive papillae with long peduncles. Nine to eleven short, digitiform ampullae are on each side of the larva. The sensorial vesicle is mid-dorsal, with the statocyte somewhat anterior and ventral to the ocellus (
Fig. 3E
).
Remarks
Although this species is being described from one single colony, its characters were different enough from those of other known species.
Leptoclinides lotufoi
sp. nov.
is different from the other Atlantic congeners by having the following characteristics: few spicules restricted to the surface of the colony, few testicular follicles and turns of the sperm duct, and many ectodermal ampullae in the larvae. A few other species of
Leptoclinides
can have many ectodermal ampullae. The Australian
L. brandi
Kott, 2001
has a granular colony surface with a high density of spicules and smaller larvae with eight pairs of ampullae.
Leptoclinides durus
Kott, 2001
has many spicules and larger larvae with eight pairs of ampullae.
Leptoclinides echinus
Kott, 2001
has more testicular follicles (about 15) and larger larvae with eight pairs of ampullae. From
New Caledonia
,
L. multipapillatus
Monniot, 1989
has more testicular follicles, more turns of the sperm duct and more than 20 ectodermal ampullae (
Monniot 1989
;
Kott 2001
).
Distribution
Type locality:
Brazil
:
Rio de Janeiro
.